1. Technical Field
The present invention relates to a nanoporous film, and more particularly, to a method of preparing a nanoporous organic-inorganic hybrid film in which organic materials and inorganic materials are hybridized, a nanoporous organic-inorganic hybrid film prepared by the method, and a nanoporous separator using the nanoporous organic-inorganic hybrid film.
2. Description of the Related Art
Nanoporous materials have recently been developed in various fields and refer to materials having pore properties due to dispersion of meso- or micro-sized small pores. Owing to their structural characteristics or wide surface area properties, nanoporous materials are actively considered for use in new fields, such as environmental materials, new catalysts, tissue engineering, and the like. Such nanoporous materials have been prepared in various ways using organic materials, inorganic materials, or organic-inorganic hybrid materials obtained by mixing organic materials and inorganic materials, and the like.
Thereamong, organic-inorganic hybrid materials refer to composite materials formed from organic materials and inorganic materials having different properties. Organic-inorganic hybrid materials are composite materials formed from organic materials, which have high flexibility, processability, low hardness and heat-sensitive properties, and inorganic materials, which have low flexibility, high hardness, strength and heat resistance, and can impart high functionality by controlling the size of a dispersed phase to nanoscale.
In the related art, various studies have been made on nanoporous films comprised of organic-inorganic hybrid materials for providing conductivity and porosity of inorganic materials through introduction of inorganic particles in a solid phase into a polymer matrix which is an organic material. However, during a process of introducing the inorganic particles having a solid phase into the polymer matrix, crevices generated at interfaces between the polymer matrix and the inorganic particles generate defects, thereby making it difficult to produce high quality nanoporous films comprised of organic-inorganic hybrid materials. Moreover, since it is not easy to uniformly disperse the inorganic particles in the polymer matrix, there is a restriction in forming a plurality of nanoscale pores and an inner structure in which the pores are connected to each other through a three-dimensional fine network.